Steam turbines are used for generating electrical energy. In normal operation, a steam is generated in the steam generator and channeled to the steam turbine to an inflow region. In the steam turbine, the thermal energy of the steam is converted into mechanical rotational energy of the rotor. However, operating states are possible where more power is required of the steam turbine, this being ensured by using an additional firing system in the steam generator that leads to an increase in the steam mass flow. This increase in the steam mass flow is fed into the steam turbine in a known manner via overload inflow regions situated downstream in the blading region. For this purpose, a branching of the fresh-steam line is established which is fluidically connected downstream to the overload inflow region.
In this overload line there is arranged an overload valve which is closed in the normal situation. A quick-closing valve and a control valve are arranged in the fresh-steam line. In some embodiments, the overload valve is arranged below the steam turbine, resulting in unnecessary additional pipeline connections. In addition, the overload valve and the pipelines have to be held, which constitutes additional outlay. The overload valve is positioned below the center of the turbine, with the result that the drainage of the overload valve becomes an absolute low point and thus makes a drainage station absolutely necessary.